Magneto with rotating magnets



April 9, 1935. 1.. BEEH MAGNETO WITH ROTATING MAGNETS Filed Feb. 10, 1934 !NVENTOR u/s Bee 2 ATTO R N EY- Patented Apr. 9, 1935" MAGNETO WITH ao'rA'TmG MAGNETS Louis Beeh, Longmeadow, Mass.,' assignor to United American Bosch Corporation, Springfield, Mass., a corporation of New York Application February 10, 1934, Serial No."710,66't' 6 Claims. (Cl. 171-252) This invention relates to magnetos of the type having rotating magnets, and has for its principal object to provide a simple, inexpensive and rigid structure having its rotating parts of small 5 size and weight, andalso having the parts of the rotor disposed in perfect balance.

\ An object'is to provide a rotor consisting of one-ormore flat bar magnets of high coercive force each having its width along the axis of rotation positioned in a manner which may be easily and cheaply assembled and held in place.

A further object is to provide a novel form of stator adapted to cooperate with the rotor and providing a magnetic circuit which is laminated throughout and in which the joints ofier a low magnetic reluctance. To this end the stator has end portions forming annular yokes built up of laminated rings, laminated pole pieces projecting therefrom in intermeshed relation.

These-and other objects will .be more fully explained in the following detailed description, wherein the preferred form of the invention, illustrated in the accompanying drawing forming part hereof, will be fully set forth. In the drawing, one specific form of the devicewill be shown but it will be understood that the invention is not limited to said form and that the same may be embodied in other forms without departing from the invention.

Referring to the drawing, Fig. 1 shows a side elevation, partly in section and partly broken away, of one form of magneto embodying this invention; Fig.2 shows a cross sectional view,-

taken on line 2'2 of Fig. 1; Fig. 3 shows a longitudinal sectionthrough the rotor, parts being shown in side elevation; and Fig. 4 shows in perspective one form of the annular yoke with the attached poles, and a portion of the winding core.

Reference numeral l0 indicates one of the annular yoke members having pole pieces H, 12 and I3 projecting at right angles from the plane thereof A similar annular yoke member I 4 is provided having corresponding pole pieces l5, l6 and I1 projecting therefrom to intermesh with the pole pieces ll, l2 and i3; The annular member I0 has a projection 18 extending therefrom in the plane thereof. Yoke member I4 is provided with similar member [9. These two members are connected by a core 20 which carries an induction coil 2|.

From Fig. 4 it will be seen that the annular yoke member ID is constructed of a plurality of thin sheets cut in the form of flat rings each having an integral member projecting exterlorly therefrom in the same plane.

This affords a laminated structure for the annular'yoke, together with an integral laminated projecting member for connection with the core. The pole pieces H, 12 and I3 are built up of thin sheets of magnetic material and formed at one end to provide a curved surface corresponding to the internal surface of annular yoke ill. It will be seen that-all of the laminations of the pole pieces Y nular yoke member Ill and that the pole pieces l5,

l6 and H project therefrom to intermesh in the proper spaced relation with the polar members H, 12 and i3.

The rotor, indicated generally at 22, has a flat bar magnet 23 which is considerably wider in the direction of the axis of rotation than its thickness, its width being substantially more than half of its length. Adjacent the respective ends of the magnet are end flanges 24 and 25 provided with axial projections 26'and 21 forming spindles which are journaled in suitable bearings for rotation of the magnet within the stator. Grooves 28 and 29, milled in the faces of, flanges 24 and 25, are substantially of the same width as the thickness of the magnet 23 and serve, together with laminated pole shoes 30 and 3! which are held between the flanges 24 and 25 by means of rivets 32, to hold the magnet firmly in position but without pressure thereon and without rivets or other fastening means extending therethrough.

The above described construction of the rotor provides a structure which is extremely simple to assemble, involving but five parts, that is the magnet 23, the two end flanges and the two pole shoes. It likewise provides a highly efficient construction for use in connection with magnets of high coercive force and of suitable dimensional proportions. In practice thestator, formed of annular yoke members It) and M, will be cast rigidly in some non-magnetic material forming an external casing or housing for the magneto. In the case of a magneto of the timer type driven at cam shaft speed and designed for a sixcylinder four-cycle engine, the pole pieces ll, l2 and I3 of one annular yoke member intermeshing with pole pieces l5, l6 and H of the opposite yoke member, provide six poles through which the magnetic flux in the core 20 is reversed six times for each two revolutions of the engine, that is when the N pole of the magnet 23 is adjacent pole I5 of yoke M, the S pole of the magnet will be adjacent pole H of yoke 18. The magnetic circuit will then be through the yoke l0, core 20 and yoke M and pole l2. Upon rotation of substantially 60 in clockwise direction in Fig. 2, the N pole will'then be opposite pole I3 ofyoke I I), while the S pole will be oppo'site pole [6 of the annular yoke member I 4, thus reversing the magnetic flux in the core 20 with each 60 of rotation of the magnet. j The reversal of flux in core 20 induces a current in the primary of the induction coil as in conventional constructions. The interrupting and distributing mechanisms may be of suitable well known forms.

In the above descriptions, I have disclosed but one magnet extending across the rotor, but it will be readily understood that a. plurality of such magnets disposed side by side may be used provided the thickness of the magnet remains relatively small in comparison to its width.

Having thus described the invention, what is claimed as new is: 1

1. A stator for dynamo electricmachines comprising a pair of annular yoke members of laminated structure having separate laminated pole pieces projecting therefrom in intermeshed relation, a laminated core connecting said annular yoke members and an induction coil upon said core.

rs projecting from said annular yoke members 2. A stator for dynamo electric machines com-v prising a pair of annular yoke members havingseparate pole pieces projecting therefrom at right angles to the planes of said yoke members, mem-" in the plane thereof, amagne tic core connecting said last mentioned members andan induction coil upon said core. I

3. A stator for dynamo electric machines including a pair of laminated annular yoke members, pole pieces projecting therefrom at right angles to the planes of said yoke members, said axis of rotation considerably greater than its thickness, end plates for said magnet and pole shoes extending across the poles of said magnet and riveted to said end plates.

-5. A stator for dynamoelectric machines including a pair of laminated annular yoke members, pole pieces projecting therefrom in'intermeshed relation, members projecting from said yoke members in the plane thereof, a laminated magnetic conductor connecting said last mentioned projecting members, and an induction .coil on said magnetic conductor.

,6. A rotor for dynamo electric machines in-,

eluding in combination a flat bar magnet of high coercive force extending diametrically across said rotor having its width in the direction of the axis of rotation considerably greater than its thickness, end plates for said magnet, and pole shoes extending across the poles of said magnet and secured to said end plates.

' LOUIS BEEH. 

